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valve clearance

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I am in the process of overhauling my spare b&s model 19 to put in a B-1. things have been going along well until yesterday. I had the cam in and was going to put the intake valve in. but when I pushed the valve down, with the cam rotated to the valve-closed position, the gap was over .024. specs say that .009 is the max (b&s out of production manual, pg 4-3 [actually does NOT list model 19 but 14 and 23 are close enough, I hope])

pulled the cam out and got the Verniers to see- it's in spec as are the tappets. also tore down another model 19 and everything there matches the motor under work.

book says to grind the valve seat to lower clearance. I don't have the tools to do this or the cash to have someone else do it.

what will be the effect on the way the motor runs if I put it back together like this? I know not enough clearance will keep the valve from closing all the way and therefore not holding compression.

the second motor had good valve clearance but needs rings and the crank is scored, as are the bearing/end plates. I may have to do a mix and match.

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You will surely get noise with that excessive clearance. It would probably run ok, but who knows for how long, and probably would beat on the lifter and cam enough to ruin one of those components.

The 14 is the same but not he 23.

I have the tools and parts so just do them by the book.

You could also have the valve ground to lower it to the clearance specs but the discard spec on the "margin" is 1/64". I would not think a shop would charge a whole lot to grind the seat or valve.

Would you believe that valve is still available from Briggs ? It is p/n 23836 for around $25.00. They are made longer so you can grind the stem to get your clearance. If the counter person balks get them to put it in the computer.

You could also pull both valves and lifters, even the cam, from your other engine and you might get lucky and some combination might be long enough. You can use either valve in the intake hole but not vice versa. Briggs ended up superceding most intake valve numbers to the exhaust number in the engines that had matching size valves.


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gary, what I have is;

motor 1 intake

nos 23836

markings on back of valve



RMC IN 18 I may have saved the wrong valve and tossed the original exhaust

both have 2 dimples on the face

motor 2

marking on back of valve

intake IN T no dimples in face

exhaust T one dimple in face with + in it

someone was inside this motor- the piston is on the rod backwards.

can you tell from this what I have? is the 23836 the newer valve that is interchangeable? the parts breakdown that I have is the one that came with the B-1 in '61. it lists the intake as 23836 and the exhaust as 23835. the sketch shows 2 dimples in the face of each.

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